1. Field of the Invention
This invention relates generally to apparatus for use in construction of commercial, industrial, and residential buildings, and more particularly, to a multi-function layout square of modular construction which contains bubble levels and a laser and is capable of being used for a variety of different tasks.
2. Brief Description of the Prior Art
During the course of constructing commercial, industrial and residential buildings, various different multi-purpose layout squares are employed. Generally, each tool is used to address one task. For example, during construction of a roof, a construction worker will use a framing square, a rafter square, a level, a gauge, a ruler, a plumb bob, and in some instances, a compass to scribe the cut line for arcs or circles. Because of the number of different tools that must be transported to the work site, and carried by the construction worker, a single multi-purpose layout square that is capable of being used to accomplish multiple tasks has been sought
There are several patents that disclose various levels having a laser light source and combination squares having a pivotal blade, or protractor, however none have the combination of structural and functional features of the present invention working together as a whole and which is capable of being used as a level, a plumb bob, a ruler, a framing square, roofing framing square or rafter square, and a gauge or scribe for straight lines, arcs, or circles.
Hochman, U.S. Pat. No. 2,054,420 discloses a combination drafting implement comprising a flat protractor with a flat scale superposed thereover and pivotally connected thereto for rotational movement relative to one another. The scale has a series of small apertures for receiving the sharp point of a pencil.
Terenzoni, U.S. Pat. No. 5,446,969 discloses a combination square and multi-purpose hand tool having an L-shaped body with a blade portion and a handle portion fixed perpendicular to the blade portion. A plate having an arcuate slot is pivotally attached in an elongate slot in the blade portion and extends from an outermost position parallel to the handle portion to an inner position folded against the blade portion. The plate moves with respect to the perpendicular leg (handle) of the L-shaped body to function as a clamp or as a caliper. Bubble levels are mounted in the pivotal plate. There is no laser beam light source, nor would it be possible for Terenzoni to be used as a plumb bob.
Webb, U.S. Pat. No. 5,519,942 discloses a device for performing leveling and transit functions having an elongated member with parallel spaced-apart top and bottom flat surfaces separated by a thickened web that includes several cutouts exposing bubble indicators arranged in a variety of orientations and includes a rotary module at one end movably mounting a laser beam generator. The rotary module has a passageway conducting a laser beam to a selected one of several slots or passageways provided in the end of the member. The web includes a housing adjacent to the rotary module enclosing electrical circuits, battery power supply and button controls for operation of the laser. A pivoting panel is coextensive with the top flat surface in a stored position while pivotal to a position normal to the top flat surface when used as a corner square. A thumb adjustment screw protrudes from the web through a flat surface to angle the device if desired.
The present invention is distinguished over the prior art in general, and these parents in particular by a multi-function layout square of modular construction having a laser that is capable of performing multiple functions. The multi-function square has a metallic outer casing with magnetic properties, with a protractor plate slidably, pivotally, and removably attached by thumbscrews to the casing that can be moved and rotated with respect to the casing and slid linearly along a portion of the length of the casing. When the protractor plate is removed the casing may be used as a level, a plumb bob, a ruler, and a compass. When the protractor plate is attached the tool may be used as a framing square, roofing framing square or rafter square for making rafter layouts, angle line cuts, seat notches (birds mouth), and a gauge or scribe for straight lines, arcs, or circles. The laser, a switch, and a pair of bubble level vials are contained in a module installed at one end of the casing, and a second module containing batteries is removably installed at the other end of the casing. Each module has electrical contacts that engage the interior surface of the casing and contacts that engage the batteries when the modules are installed and abutted. When the switch is on, a circuit is completed through the metallic casing, which electrically connects the batteries to the laser. The casing may be suspended vertically from a support surface by passing a string or wire through a bore in one of the thumbscrews, may be mounted on a tripod, or may be magnetically attached to metal objects.